tranny short shifting problem
 

87 GTA with Rebuilt 700r4 almost 4000 miles on it, the problem im have is that the tranny shifts to soon wont hold the gears (doesnt slip) 1st to 2nd shifts about 4800 to 5000 rpm 2nd to 3rd shifts about 4000 and then from 3rd to over drive it shifts about 3500 rpms.Kick down cable is set to its proper position,I brought the car back to the transmission shop and he told me it was the LT4 cam in the engine the power band was now different then factory? I had cams in cars before, but never had a problem like this,can any help me out?

Each valve body and governor is calibrated specifically for the application. It sounds like you got a rebuilt trans from a different vehicle.
If the guy knew what he was doing he could change some springs in the valve body and change the governor.